hows your plumbing?

hey everyone im new and in the seattle area. i was wondering the best way to set up all the plumbing for a octotank. i have read alot about it, but im more of a pictures kinda guy. if you could maybe show some photos of how you setup your tanks and the best way to do it for an octo only species tank.

ok, my peoples. i scanned the forums and found lots of useful info, but nothing that really showed me how to set up my sump. my tank is a 37 gallon and i have a heater(if needed) and skimmer that i would like to set up in a 10 gal sump if possible? im just wondering how to set up my tank to be most effective for a octopus. (escape proof) also, what kind of filtration would i need? i was thinking just using live rock for my biofilter and the skimmer would take up the rest. any ideas or photos would be sweet!

Do you have the height for a skimmer under the stand any way then? Unfortunately, a 5 gallon tank won't give you enough water depth to run a skimmer, a return pump and allow room for the pump off back flow from the tank. A 10 gallon pushes the minimum limit as it is.

Sweet, i got my 10 gallon to fit... My skimmer fits in there too. Is there a formula for figuring out what kind of overflow box to use with your return pump? Im trying to do this all my self to save some moolah.

Your best bet is to pick up a good reefkeeping book or check in with the local reef scene. Without more detail, I am not sure how much we can help you since every system is 'custom'.

For instance, what do you mean by overflow box? Internal or External? Full height or shorty? For octos, I actually don't like overflow boxes and prefer to put some bulkheads through the back top of the tank, and make or buy perforated strainers or cover them with open cell foam.

I have an acrylic top that I bolted down to the top rim of my tank. I glued square acrylic rod to the underside of the top just over the "teeth" in my overflow, to fill the gap between the top of the teeth and the tank lid. The slits on my overflow are 1/8" wide, so I can't keep a really small octopus in there, but any octo with an eyeball larger than 1/8" should be fine. For a smaller one I would cover the top edge of the overflow with some open-celled foam (like the foam blocks used in AquacClear filters, that water flows through easily). You would need to be able to remove and rinse the foam periodically. If the foam clogs and blocks your overflow, your pump will try to put your whole sump into your tank (onto your floor).

Your live rock will be in the display right, not in the sump?

You only need to cycle the volume of your tank through your sump four or five times per hour, so a return pump that moves 150 - 250 GPH, at whatever head pressure you'll have, is what you should design for (A pump rated for 350 - 600 gph should be in the ball park). More than that is unnecessary, and requires your overflow to be larger. Use Koralias or a closed loop to get more flow in the tank.

Wow, everyone is this forum is so helpful. What do you mean head pressure? I appreciate all the help, u guys rock! And yeah my live rock will be in the display tank. Probly 45lbs, will that cramp up my tank too much?

"Head pressure" is the total pressure the return pump must work against to get water back to the tank. It is measured in feet, because it is mostly determined by the vertical distance that the pump must lift the water to get it up to get it from the water level of the sump, to the water level of the display tank. Because of the resistance caused by plumbing, total head is usually the vertical distance between the water lines plus about 10 or 15% of that distance. The flow rate of any pump is advertises assuming 0 head, so a pump that is rated at "425 gph" will put out 425 gph under ideal conditions and only if it isn't lifting the water above where it is getting it. The actual flow (in gph (gallons per hour)) decreases as the head (vertical lift distance) increases, so you can plot a curve, on a graph, of gph vs. head. The flow of some pumps decreases a lot faster than others as the head increases, so you need to look at the flow curve (or flow graph) for each pump you are considering, and see how much flow it will deliver at the head (vertical distance) that your system will have.

So from the bottom of my stand (where i will put my sump) to the top of my tank is 4ft. What should i shoot for as far a gph of my pump? and should i choose an overflow box that is about 300-400 gph?

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I'm thinking a Quiet One 1200 pump, and an overflow that can easily handle at least the 218 gph that it will deliver. A 25% less powerful pump would also be fine. Here's how I got those numbers:

Head distance should be measured from the waterline inside your sump (in the chamber your return pump draws from) to the waterline in your display tank. So if your sump is 6" deep, and the water in your display is 1" below the top edge of your tank, then you have 41" of vertical lift (head) which is 41/12 = 3.4 feet. Assuming that you are using plumbing that doesn't cause much restriction (like 3/4" or 1" inside diameter) you can add 5% and call it 43" of head, 3.6 feet. You have a 37 gallon tank, and the rule of thumb (I think) is that you want to run four of five times your tank volume through your sump per hour, so you want a return pump that will deliver between 150 and 185 gph at 3.6 feet of head. As pumps age and get dirty, they move less water, and the curves might be optimistic, so err on the high side. You can use Google and try to find the output curve (graph) for each pump that you are considering, and find one that says it delivers between 175 and 200 gph at 3.6 feet of head. An easier way to go would be to use one of the online head calculators. Enter your actual head distance (3.4 feet) and some specifics about your plumbing, and pick a pump from the list (all the pump curves for the listed pumps have been entered into the host computer and the calculator uses them to look up your output flow in gph. Keep picking different pumps until you find one that delivers the right amount of flow using the values you've entered. For example, It says that a Quiet One 1200 will deliver 218 gph at 3.48 feet of head (err on the high side). You would then know that your overflow must be able to easily handle 218 gph. If you want more flow inside your tank (which you probably will) I suggest you use a Koralia Nano, which delivers 240 gph. Add that to the 218 you get from your return pump, and you'll have (in Theory) 458 gph of flow in your display. That's 12 times the volume of your tank, which is more than enough (maybe too much for an octopus).